Apparatus for removing stuck pipe from well bores



Aplii] 29, 1958 N, H, HALL 2,832,423

APPARATUS FOR REMOVING STUCK PIPE FROM WELL BORES Filed June 1. 1954 2Sheets-Sheet 1 M A/o/ h. f/a// INVENTOR.

/4a 1 /5 BY%. Z. M

ATTORNEYS April "29, 1958 N. H.-HALL 2,832,423

APPARATUS FOR REMOVING STUCK PIPE FROM WELL BORES Filed June 1. 1954 2Sheets-Sheet 2 c4 27a i U 22 Nob/e H. /7 7// l INVENTOR.

l BY ii 6 fun-L v ATTORNEYJ the well. end, which is of suflicientinternal diameter to pass over United States Patent APPARATUS FORREMOVING STUCK PIPE FROM WELL BORES Noble H.Hall, Shreveport, La.Application June 1, 1954, Serial No. 433,430

Claims. (Cl. 166-221) This invention relates to new and usefulimprovements in apparatus for removing stuck pipe from well bores.

This invention is an improvement on the apparatus disclosed in myco-pending U. S. application, Serial No. 272,593, filed February 20,1952, now Patent No. 2,739,351.

An object of this invention is to provide a new and improved apparatusfor removing stuck pipe from well bores, which is of a simplifiedconstruction as compared to the apparatus disclosed in the aforesaidco-pending application.

An important object of this invention is to provide a new and improvedapparatus for removing stuck pipe from well bores, wherein a greatercontrol is provided for the circulation means than in the apparatusdisclosed in the aforesaid co-pending application.

Another object of this invention is to provide a new and improvedapparatus for removing stuck pipe from a well bore, wherein saidapparatus has an improved clutching arrangement for attaching theapparatus to a stuck pipe, for rotating a wash pipe of the apparatuswhile circulating fluid after the apparatus has been attached to thestuck pipe, and for releasing a safety joint to permit removal ofsubstantially all of the apparatus from the well in the event the stuckpipe is not removed from the well by the apparatus.

The construction designed to carry out the invention will be hereinafterdescribed together with other features thereof.

The invention will be more readily understood from a reading of thefollowing specification and by reference to the accompanying drawingforming a partthereof, wherein an example of the invention is shown, andwherein:

Figure l is a view, partly in elevation and partly in section,illustrating the apparatus of this invention as it is lowered into thewell bore.

Figure Z is a view, partly in elevation and partly in section,illustrating the portion of the device taken on line 2-2 of Figure 1 inan enlarged view.

Figure 3 is a horizontal sectional view taken on line 33 of Figure 2.

Figures 4 and 4A are views, partly in elevation and partly in section,which illustrate the upper and lower portions of the apparatus or toolof this invention, respectively, when the parts are in the circulatingposition after the tool has been connected to the stuck pipe or fish.

in the drawings, the letter T designates generally the apparatus or toolof this invention for removing a stuck pipe or fish from a well bore.The stuck fish is illustrated in Figure 4A as a stuck pipe A, which hasa threaded box A. The fishing tool or apparatus T is adapted to belowered into a well bore on a tubing string or retrieving pipe 11 whichextends from the surface of The tool T has a wash pipe 12 at its lowerand surround the stuck pipe or fish A. Inside of the Wash pipe 12, acoupling member 14 is provided which has an external threaded pin 15which is adapted to be threaded into the threaded box A of the stuckpipe or fish A upon a rotation of the tool T. As will be explained indetail, fluid circulation can be maintained through the fishing tool Tprior to the time that the pin 15 is connected to the fish A; andsubsequently to the making of such connection the circulation can becontrolled so that iiuid will either pass into the bore of the stuckpipe A or inside of the wash pipe 12 and outside of the fish A tofacilitate loosening of the stuck pipe or fish A. Also,

the tool is so constructed that the wash pipe 12 can be rotated andmoved longitudinally during circulation after the connection is madebetween the pin. 15 and the stuck pipe or fish A to thereby preventsticking of the wash pipe 12.

The external body 16 of the tool T includes a number of tubularsections, namely, an upper sleeve 17 which is connected to the lower endof the tubing string or retrieving pipe 11, a tubular sleeve 18,connected to the lower end of the upper sleeve 17, a tubular clutchmember 19 connected to the lower end of sleeve 18, and a tubularconnecting sleeve 20 connected to the lower end of the clutch member 19and the upper end of the wash pipe 12. It can thus be seen that there isdirect connection through the body of the tool T from the tubing or pipe11 to the wash pipe 12. If desired, an annular weld 21 may be providedbetween the sleeve 17 and the sleeve 18 in addition to the threadedconnection thcrebetween. One or more screws 23 lock the sleeve 18 to theclutch member 19. A usual annular friction ring 22 which is flaredinwardly is seated at the upper end of the sleeve 20 to facilitatedisconnection of the right hand threaded connection between the sleeve20 and the clutch member 19 in the event the wash pipe becomes stuck inthe well bore. The ring 22 is preferably formed of hardened steel withthe upper face 22a and lower face 221) knurled, Seal rings 24 and 25 ofrubber or similar material are positioned between the upper and lowerthreaded connections, respectively, of the clutch member 19 with thesleeve 18 and the sleeve 20.

The coupling 14 is carried by a mandrel 27 which is disposed within thebody 16 of the tool T and which is longitudinally movable relativethereto, as will be explained. The lower end of the mandrel 27 hasexternal coarse or fast left-hand threads 28 which are threadedlyengaged with corresponding inwardly extending coarse or fast left-handthreads 29 in the upper end of the bore of the coupling 14, whereby areleasable connection is provided between the coupling 14 and themandrel 27. The left-hand threads 23 and 29 may be of the Acme type orany other similar type. The upper end of the mandrel 27 is formed withan enlarged head 31 and with a plurality of spaced outwardly extendingsplines 32 therebelow. A coil spring 33 or similar resilient membersurrounds the head 31 and is secured thereto by a small pin 3 9 or thespring 33 is fitted to the head 31 so tightly that it will not falldownwardly by its own weight. The spring 33 is thus secured to the head31 with its upper end abutting an annular flange 31a, and it. will beobserved that the lower end of the spring 33 does not extend down to theshoulder 19a on the clutch member 19. The enlarged head 31 carries aseal ring 35 of rubber or other resilient material which provides a sealbetween the upper end of the mandrel 27 and the bore of the sleeve 13,whereby fluid directed downwardly through the tubing string 11 will allflow into the bore 27a of the mandrel 27 rather than externally of themandrel 27. During the lowering of the tool T into the well bore,circumferentially spaced upwardly directed lugs 40 on the upper end ofthe coupling 14 are in interfitting engagement with circumferentiallyspaced downwardly directed lugs 41 on the lower end of the clutch member19, whereby the assasas coupling 14 and the outer tubular body 16 arelocked together so that rotation of the tubing or pipe 11 is transmitteddirectly to the coupling 14 to attach the pin 15 on the coupling 14 tothe fish A. A siear pin 42 extends through. One lug 4i) and through anadjacent lug 41 to hold the lugs 4d and 41 in their interfitted positionduring the lowering of tool into the well bore. When the pin 42 issheared, the body 16 can then be moved upwardly relative to the mandrel27. Should the pin 42 shear prematurely during the lowering operation,the mandrel 27 and spring 33 wiil move downwardly relative to the body16 until the lower end of the spring 33 contacts the shoulder 1% and iscompressed slightly. The spring 33 is of sutficie nt length and stren thto prevent the engagement of the splines 32 and 5h, so that actuallyspring 33 is only a safety feature and could be eliminated.

After the coupling 14 has been attached to the fish A, the tubing string11 can be raised to shear the pin 42 (if not prematurely sheared) and todisengage the lugs 40 and 41 (Figures 4 and 4A) to thereby permitrotation of the body 16 and the wash pipe 12 relative to the mandrel 27,the coupling 14 and the fish A. Then the outer body 16 can be furtherraised relative to the mandrel 27 to place the mandrel 27 in a fullyextended position and to cause the splines 32 to engage with inwardlydirected splines 50 in the upper end of the clutch member 19. When thesplines 32 on the mandrel 27 are engaged or interfitting with thesplines 50 on the clutch member 19, the mandrel 27 is locked to the bodyof the tool T whereby a rotation of the tubing string 11 in a right-handor clockwise direction (as viewed from the top of Figure 1) will causethe mandrel 27 to rotate relative to the coupling 14- and will therebycause a disengagement of the left-hand threads 2? and 29. Such releasethereby permits the removal of the entire tool T from the well bore,except for the coupling member 14 which remains in position on stuckfish A. It will therefore be apparent that the threaded connectionprovided by the coarse threads 28 and 29 is actually a safety joint.

Circulating ports 52 are provided in the wall of the mandrel 27 forpermitting circulation of washing fluid from the tubing string 11downwardly through the bore 27a of the mandrel 27 and then through theports 52 1 into the annular space between the wash pipe 12 and thecoupling 14 (Figure 4A) when the outer body of the tool T is in theaforesaid intermediate position with respect to the mandrel 27 andwherein the lower end of the clutch member 19 is above the ports 52 andneither the splines Sit and 32 or the lugs 40 and 41 are engaged. Whenthe parts are in such intermediate position the Wash pipe 12 can berotated or moved longitudinally independently of the coupling 14 whilemaintaining the fluid circulation around the stuck pipe or fish A,whereby sticking of the wash pipe 12 is prevented. Also, fluidcirculation through the ports 52 can be closed by lower ing the tubularbody 16 to position the lower end of the clutch member 19 below theports 52 whereby fiuid is then directed to the bore of the stuck pipe orfish A.

In the operation or use of the tool or apparatus T, it is lowered intothe Well bore on the tubing or retrieving pipe 11 with the parts in theposition illustrated in Figures 1-3. The shear pin is of suflicientstrengt. to maintain the mandrel 27 in its raised position with the lugsit} and 41 interfitting to prevent relative rotation of the coupling 14with respect to the tubing string ill and the body of the tool T. Duringsuch lowering, circulating or washing fluid is conducted downwardlythrough the tubing or pipe 11 and thus through the bore 27a of themandrel 27 for discharge into the well bore through the bore lila of thecoupling 14. it will be noted that the circulating ports 52 are closedduring such lowering operation and are sealed by a seal ring 53 ofresilient or rubber material which is positioned below the ports 52 andbetween the mandrel 27 and the clutch member 19.

When the tool T has been lowered into the well bore a sufiicientdistance to reach the upper end of the stuck pipe or fish A, the washpipe 12 passes around the stuck pipe A and continued lowering of thetool T permits the pin to contact the threaded box A of the fish A. Thepin 15 is then threaded into the box A by rotating the tubing string 11to the right or clockwise (as viewed from above the tool in Figure 1) sothat the coupling i4 firmly connected to the stuck pipe or fish A.Thereafter, the tubing string 11 is raised or lifted to shear the pin 42and to disengage the lugs 40 and 41 to thereby raise the body 16relative to the inner mandrel 27 so as to move the lower end of theclutch member 19 above the circulating ports 52 whereby circulation offluid from the bore 270! can be conducted through the ports 52 andintothe wash pipe 12. The length of the mandrel 27 is such that when theports 52 are exposed, the lugs 1-h and 41 are disengaged and likewisethe body 16 of the tool T has not been raised sufficiently to engage thesplines 32 and 50. Thus, rotation and longitudinal movement or thetubing or pipe 11 can be imparted to the wash pipe 12 to move same whilecirculating the fluid downwardly through the ports 52 into the annularspace between the stuck fish A and the wash pipe 12. This prevents thesticking of wash pipe 12 during such circulation. If it is desired tocirculate down through the fish A after the connection therewith hasbeen made, the ports 52 are closed by lowering the pipe 11 to positionthe clutch member over the ports 52. It is therefore believed evidentthat control of fluid flow through the ports 52 is obtained with thetool T of this invention.

While the Wash pipe is maintained in movement, an explosive charge islowered into the bore of the tubing string 11 and downwardly through thebore 27a of the mandrel 27 into the bore of the stuck pipe A to aposition opposite a desired coupling (not shown) in the stuck pipe Awhich it is desired to loosen for release of the stuck pipe A from theremainder of the pipe therebelow.

Prior to the time that the explosive charge is fired, the retrievingpipe or tubing 11 and the tubular body 16 including the parts 17, 18,19, 20 and the wash pipe 12 are moved or raised upwardly to cause thesplines 50 and 32 to interfit or engage to provide a positive rotativecoupling between the tubing string 11 and the mandrel 27. Thereafter, anupward tension is taken on the pipe 11 and a left-hand torque is appliedto the pipe. This torque is sufficient to apply a left-hand torque tothe stuck pipe A and when this accomplished, the explosive charge isfired. As is well known, when an explosive charge is fired adjacent acoupling and a left-hand torque is placed in the stuck pipe, the threadsare sufficiently released so that they become disconnected from theportion of the stuck pipe therebelow. When the upper portion of thestuck pipe A has thus been released from its connection to the portionof the stuck pipe therebelow, then the entire tool T can be removed fromthe well bore with the released portion of the stuck pipe A connectedthereto by the connection of the threads 15 in the box A. It should bepointed out that when the threads 15 are made up in the box A, they areturned very tightly so that a tight connection is made which does notrelease when the lefthand torque is put in the stuck pipe A.

It is also pointed out that the left-hand coarse threads 28 and 29 onthe mandrel 27 and the coupling 14 transmit the left-hand torque to thecoupling 14 and thus to the stuck pipe A. Thus, when the left-handtorque is being applied, the connection made by the threads 28 and 29 isin fact being tightened and this will assure that there will be nobreaking out of this connection during the application of the left-handtorque. The threads 28 and 29 also provide a safety joint so that in theevent the stuck pipe cannot be removed and the threads 15 cannot bedisengaged or disconnected from the stuck pipe A, a rotation of theretrieving pipe 11 and the mandrel 27 in a right-hand direction willresult in a release or breaking out of the threads 28 from the threads29. This will permit the removal of the retrieving pipe 11, the mandrel27, the tubular body 16 of the tool T, and the wash pipe 12. In fact,only the coupling 14 will remain in the well bore with the stuck pipe orfish A, so that substantially the entire tool T is removable from thewell bore even though the stuck fish A is not released when theexplosive is fired.

In the event the wash pipe 12 becomes stuck in the well bore after thecoupling 14 is connected to the stuck fish, then the threaded connectionor safety joint between the clutch member 19 and sleeve 20 isdisconnected by a left hand rotation which is of course effected whenthe splines 32 and 50 are disconnected and, preferably after the threads28 and 29 are disconnected. When such disconnection of members 19 and 20is thus effected, the coupling 14, sleeve 20 and wash pipe 12 are leftin the well.

The foregoing disclosure and description of the invention isillustrative and explanatory thereof and various changes in the size,shape and materials, as well as in the details of the illustratedconstruction," may be made, within the scope of the appended claims,without departing from the spirit of the invention.

What is claimed is:

l. A well tool adapted to be lowered into a well bore for retrievingstuck pipe from the well here, including, a retrieving pipe, a tubularbody connected to the lower end of the retrieving pipe, a wash pipesuspended from the tubular body and having an internal diameter greaterthan the external diameter of the stuck pipe to be re covered, wherebyan annular space is provided between the wash pipe and the stuck pipewhen the wash pipe is positioned around the upper portion of the stuckpipe, a mandrel disposed within the body and movable longitudinallyrelative thereto within predetermined limits, coengageable means on themandrel and body for setting up non-rotative connections between themandrel and body, whereby the mandrel and body are non-rotativelyconnected at the limits of longitudinal movement with respect to eachother, attaching means on the lower end of said mandrel adapted to beattached to the stuck pipe in the well bore upon a rotation of theretrieving pipe, and releasable connecting means initially releasablyconnecting the attaching means to the tubular body and releasablewhereby said mandrel, body, wash pipe and retrieving pipe may bereleased from the attaching means down in the well and removed from thewell bore separately from said attaching means.

2. An apparatus as set forth in claim 1, wherein the co engaging meansis in connected position when the mandrel is at its upper limit oftravel relative to the tubular body, and frangible means for maintainingthe mandrel in such upper position during the lowering of the apparatusinto the well bore.

3. An apparatus as set forth in claim 1, wherein said co-engageablemeans is in connected position when the mandrel is at its upper limit oftravel relative to the tubular body, said co-engageable means beingdis-engaged upon an upward movement of the tubular body relative to themandrel, and a second co-engageable means for connecting the mandrel tothe tubular body when the mandrel is at its lower limit of movementrelative to the tubular body whereby rotation can be imparted from theretrieving pipe to the mandrel.

4. An apparatus as set forth in claim I, wherein said co-engageablemeans includes a plurality of circumferentially spaced downwardlyextending projections on said body, and a plurality of circumferentiallyspaced upwardly extending projections on said mandrel for interfittingwith the projections on said body whereby connection is establisbedbetween the body and the mandrel for imparting rotation of theretrieving pipe to the atcaching means.

5. An apparatus adapted to be lowered into a well here for removing astuck pipe from the well bore, comprising a retrieving pipe, a tubularbody suspended from the retrieving pipe, a wash pipe suspended from thetubular body and having an internal diameter larger than the diameter ofsaid tubular body, a mandrel disposed within the tubular body fortelescoping movement with respect to the tubularbody, means for limitingthe longitudinal movement of the mandrel, an attaching means on themandrel for connecting to the stuck pipe, co-engageable means on thebody and themandrel for non-rotatively connecting the body to themandrel and attaching means when the mandrel is fully telescopedrelative to the tubular body, another co-engageable means on the bodyand on the mandrel for establishing a non-rotative connection betweenthe body and the mandrel when the mandrel is fully extended relative tothe tubular body, said body being free to rotate relative to the mandreland the attach ing means when the tubular body is in .an intermediateposition between the fully telescoped position of the mandrel and thefully extended position thereof whereby rotation of the retrieving pipeis imparted to the wash pipe without rotating the mandrel or theattaching means when the body and the mandrel are in the intermediateposi tion, said mandrel having a circulating port therethrough toprovide fluid communication between the bore of the mandrel and the boreof the wash pipe when the mandrel is in any position other than asubstantially fully telescoped position whereby circulation from theretrieving pipe through the circulating port and into the bore of thewash pipe is obtained, said circulating port being closed by a loweringof the retrieving pipe and the tubular body relative to the mandrel.

6. An apparatus as set forth in claim 5, including a resilient means onsaid mandrel and located between abutments on the mandrel and body toprevent an inadvertent non-rotative connection between said mandrel andsaid body by movement of the mandrel to fully extended position relativeto the body.

7. An apparatus adapted to be lowered into a well bore on a retrievingpipe for removing stuck pipe from the well bore, including a Wash pipesupported by and suspended from the retrieving pipe, said supporting andsuspending structure being a telescoping assembly comprising an innertubular member and an outer tubular member, means connecting the membersfor limited telescoping movement with respect to each other, meansattaching the upper portion of one of the members to the retrieving pipeand the lower portion of said member to the wash pipe; whereby theassembly is suspended. from said retrieving pipe, a coupling membersecured to the lower end of that member which is not directly connectedto the retrieving pipe and having means for engaging with the upper endof the stuck pipe, a first interlocking means connected in the tubularmember which is connected to the retrieving pipe, said interlockingmeans having projections at its upper end and projections at its lowerend, a second interlocking means on the other tubular member forestablishing a non-r0tatable connection with the projections on theupper end of the first interlocking means when the tubular members arefully extended, and means on the coupling member for establishing anon-rotatable connection with the lower set of projections on the firstinterlocking means when the tubular members are fully telescoped tonon-rotatively lock said coupling member to said retrieving pipe,whereby the tubular members of the telescoping assembly arenon-rotatively coupled at the limits of longitudinal movement of themembers with respect to each other, and a releasable connection securingthe coupling member to the tubular member to which it is attached,whereby the telescoping assembly may be released from the couplingmember down in the well'and the telescoping assembly, retrieving pipeand wash pipe may be removed from the well bore independently of thecoupling member.

8. An apparatus as set forth in claim 7, together with a secondreleasable connection between the retrieving pipe and the wash pipe,whereby in the event the wash pipe becomes stuck, the retrieving pipemay be removed separately from the wash pipe.

9. An apparatus adapted to be lowered into a well bore on a retrievingpipe for removing stuck pipe from a well bore, comprising a wash pipesupported by and suspended from the retrieving pipe, a telescopingassembly comprising an inner tubular member and an outer tubular member,means connecting the members for limited longitudinal movement withrespect to each other, co-engageable means on the members for setting upnon-rotative connections therebetween whereby the tubular members of thetelescoping assembly are non-rotatively coupled at the limits oflongitudinal movement of the members with respect to each other, one ofthe tubular members connecting the wash pipe to the retrieving pipe, andan attaching means connected to the member which is not attached to theretrieving pipe for connecting the telen scoping assembly to the stuckpipe, means to control fluid circulation from the bore of the retrievingpipe to the bore of the wash pipe including a circulating port in thewall of that tubular member which is not directly connected to theretrieving pipe, said port establishing communication between the boreof the member and sealing the bore of the Wash pipe, and means to sealbetween said members to close off fluid flow through said circulatingport upon longitudinal movement of the tubular members with respect toeach other to fully telescoped position and for opening said port in allother positions of said members.

10. An apparatus as set forth in claim 9, together with a releasableconnection between the coupling member and that tubular member to whichthe coupling member is attached, whereby the telescoping assembly,retrieving pipe, and wash pipe may be disconnected from the couplingmember, and a second releasable connection between the retrieving pipeand wash pipe which permits disconnection of the retrieving pipe fromthe wash pipe, whereby these parts may be removed from the well boreseparately from the coupling member and wash pipe.

Church Mar. 14, 1950 Stewart et al. July 28, 1953

